C#生成不重复随机字符串类

本文实例讲述了c#生成不重复随机字符串类。分享给大家供大家参考。具体如下：

这个c#类用于随机产生不重复的字符串，可以指定字符串范围，可以指定要产生字符串的长度

using system;
namespace dotnet.utilities
{
  public class randomoperate
  {
    // 一：随机生成不重复数字字符串 
    private int rep = 0;
    public string generatecheckcodenum(int codecount)
    {
      string str = string.empty;
      long num2 = datetime.now.ticks + this.rep;
      this.rep++;
      random random = new random(((int)(((ulong)num2) & 0xffffffffl)) | ((int)(num2 >> this.rep)));
      for (int i = 0; i < codecount; i++)
      {
        int num = random.next();
        str = str + ((char)(0x30 + ((ushort)(num % 10)))).tostring();
      }
      return str;
    }
    //方法二：随机生成字符串（数字和字母混和）
    public string generatecheckcode(int codecount)
    {
      string str = string.empty;
      long num2 = datetime.now.ticks + this.rep;
      this.rep++;
      random random = new random(((int)(((ulong)num2) & 0xffffffffl)) | ((int)(num2 >> this.rep)));
      for (int i = 0; i < codecount; i++)
      {
        char ch;
        int num = random.next();
        if ((num % 2) == 0)
        {
          ch = (char)(0x30 + ((ushort)(num % 10)));
        }
        else
        {
          ch = (char)(0x41 + ((ushort)(num % 0x1a)));
        }
        str = str + ch.tostring();
      }
      return str;
    }
    #region
    /// <summary>
    /// 从字符串里随机得到，规定个数的字符串.
    /// </summary>
    /// <param name="allchar"></param>
    /// <param name="codecount"></param>
    /// <returns></returns>
    private string getrandomcode(string allchar, int codecount)
    {
      //string allchar = "1,2,3,4,5,6,7,8,9,a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z";
      string[] allchararray = allchar.split(',');
      string randomcode = "";
      int temp = -1;
      random rand = new random();
      for (int i = 0; i < codecount; i++)
      {
        if (temp != -1)
        {
          rand = new random(temp * i * ((int)datetime.now.ticks));
        }
        int t = rand.next(allchararray.length - 1);
        while (temp == t)
        {
          t = rand.next(allchararray.length - 1);
        }
        temp = t;
        randomcode += allchararray[t];
      }
      return randomcode;
    }
    #endregion
  }
}

希望本文所述对大家的c#程序设计有所帮助。